As communication technologies advance, serial interfaces have been widely employed in communication protocols such as Ethernet and PCI Express. For example, serial interfaces have been widely used to convert signals between parallel bus-connected devices and high-speed serial communication systems. In order to enable the movement of a large amount of data between parallel and serial systems, a serializer/deserializer is employed to convert data from a parallel data form to a serial data form in the high-speed serial communication systems.
The serial communication system in its simplest form may comprise input data streams, a transmitter, a communication channel, a receiver and output data streams. The transmitter may receive a parallel set of bits and convert them into serial signals through suitable digital circuits such as multiplexers and shift registers. The serial signals are transmitted over the communication channel to the receiver.
The data streams flowing through the communication channel may be severely distorted when the data streams are transferred at high data rates. For example, the data streams may be distorted by high-frequency losses in the communication channel. In order to reduce distortion and reconstruct clean signals, suitable signal reconstruction techniques such as signal equalization may be employed to equalize the frequency response so as to reduce the high frequency distortion.
In a serial communication system, as data rates increase, jitter has become a much more significant problem. Jitter may cause data distortion at the transmitter, in the communication channel and at the receiver. In order to further improve the system performance, it is necessary to employ a jitter attenuation apparatus to reduce the data distortion of the serial communication system.